Low Gas Pressure

I have been running no heat calls all day - today I have found lots of very low gas pressure you can run the Nat Gas hot water heater or 95% furnace. Most days I find 5" to 5.5" and higher water Column then the regulator goes down to 4" then at burner is 3.5" today at -10 outside I find 2.1" at burner and the flame rod does not keep the burner on. On the good side the BTU per burner is less and matches the load to home better, with most furnaces oversized. Down side is close to sooting up the heat exchanger. Also the high heat is not in the mid air stream so using my flue gas meter the O2 goes up and flue temp goes down and heat rise goes down. I have been looking for ways of testing gas BTU's in the feild?

Replies to This Discussion

The are having gas line constraint problems in some areas of the country. If it is impacting home heat - then they should be contacting the commercial interrupt-able users and asking that they go offline for a few days.

Or is the cold weather causing some of the old regulators by the meters to fail?

Sounds like you want an easy to use calibrated bunsen burner - with a measured amount of water... and a thermometer.... some thing easy and nearly indestructable in the field.

But honestly - it sounds like the real problem is with the utility. If you are seen lots of calls, everyone else is also seeing them... and it sounds like its just overloaded gas transmission lines.

Water in their side of the high pressure line? Interesting if so, I thought they'd have traps for that along the way at the various compressor and storage facilities. I also thought they had inline gas drying... since they often store NG in big underground salt caverns (at least in the NW), it could come in contact with moisture ... so I'm pretty sure they'd dry it as it comes out of the storage facility.

If they are getting moisture into the high pressure lines -- seeping in to the pipes.... I'd hope they are running scared about pipe explosions later when everything thaws..

If it's in the house... seems you could turn off gas, bleed off the pressure... and check one of the rust / sediment traps on the line just before it enters the furnace..

Knowing the BTU heat value is kind of interesting... but since you can't order different grades of gas to be delivered to the house - the best you really can do is use the previous months values from the bills or ask the utility what the current values are. The NG in the system and its sources is constantly changing.

Sorry to hear you're having a quality problem with natural gas in your area. The cold weather may have contributed, but it's unusual for natural gas analyses to run anything less than 98% methane(CH4). To answer your question, you must take a sample in a glass Orsat tube and submit it for analysis to a lab like Sherry BTU Lab . They will analyze it by gas chromatography, and send you a report, for a price. The other possibility is to keep calling your local gas company and ask for the lab. Although they are extremely busy, if they believe there exists enough of a problem in the field, they will send a technician out to grab a sample, and a chemist will analyze it for BTU content by gas chromatography. Good fortune. Perhaps the problem will clear as the weather warms up.

This was an experienced answer, not conjecture from someone that hasn't actually worked in the field! Most engineers will just sit in their office and smoke cherry pipe tobacco. Try to get atech on it if possible.

today 36' and rain just not a low gas today to day is 6.4" water coll coming past gas meter . I empted 4 traps/drip legs and all had lots of water in them. My thinking is when gas presser is low- water leaks comes in.

Has utility suggested where water is entering system...I can't imagine it being on the low pressure side of the meter...not in that quantity... unless it somehow runs underground... it should be above water level.

Or are the low pressure lines run under a slab from the meter to the furnaces? That seems pretty risky..

If so, They must have had some kind of fault upstream. If you are in city, I'd check with them incase they have a franchise agreement. Cities and fire districts don't like the idea of responding to CO poisoning episodes, or gas explosions this time of the year... I'd think they'd help push for some answers from utility...

Eric: OK, I get it. You are a conscientious guy trying to solve this problem for your customers. You must be right, that the low gas pressure is allowing the water in. Action Idea: call the gas company and tell them that: the gas pressure may be too low, providing an inadequate and possibly unsafe flame. If they won't respond to you telling them there is an Unsafe Condition, then go public. Contact a local consumer oriented TV station who will put some pressure on the gas company for you. Wish you great luck in solving this for your people!